Method of subbing a photographic film



Oct 28, 1969 man@ TAKENAKA ETAL 3,475,193

METHOD OF SUBBING A PHOTOGRAPHIC FILM Filed Sept. 9, 1965 HARUO TAKENAK.SEICH/ 008A 7Z'PPE/ /KED SHYN/CH ADACHIHRRA ,6MM www THE/R HTTdRN' YSUnited States Patent O METHOD OF SUBBING A PHOTOGRAPHIC FILM HaruoTakenaka, Odawara-shi, Seichi Ooba, Tokyo, and

Teppei Ikeda and Shynich Adachihara, Ashigarakamigun, Kanagawa-ken,Japan, assignors to Fuji Shashin Film Kabushiki Kaisha, Kamigawa-ken,Japan, a corporation of Japan Filed Sept. 9, 1965, Ser. No. 486,044 Int.Cl. B44d I/06, l/092 U.S. Cl. 117-34 5 Claims ABSTRACT oF THE DIscLosUREA process for subbing a photographic film, which comprises radiatingultraviolet rays having a wave length of l800-3200 A. for up to 3minutes upon a film support of biaxially oriented, crystallized linearpolyester containing aromatic carbonyl groups, in the presence of atleast one member selected from the group consisting of oxygen and ozone,and then applying to the radiated surface a subbing solution containinggelatin or an organic solvent-soluble hydrophilic resin, said gelatinand resin being in a mixed organic solvent containing 1-25% by weight ofa .member selected from the group consisting of solvents and swellingagents for the polyester, whereby adhesiveness between the film supportand the emulsion layer or the backing layer of the photographic lm isremarkably improved.

This invention relates to a method for the production of a photographicfilm, and more particularly, to a method of subbing a photographic film.

In general, photographic film is produced by applying a hydrophiliclight sensitive emulsion layer and a hydrophilic back layer to ahydrophobic film as support.

It is required that the adhesion of the emulsion layer or back layer toa film support be strong enough not to be stripped during theproduction, processing, and use of the photographic film under dry andwet conditions. For this purpose, an adhesive layer called a subbinglayer is ordinarily provided between the film support and the emulsionlayer and back layer (bath being designated as the emulsion layerhereinafter).

Up to this time, it has been usual that when a film support consistingof cellulose ester is used, such subbing layer is formed by applying asolution or dispersion of hydrophilic resin in a solvent capable ofdissolving or swelling the support to the surface of the support.

However, in order that the subbing layer is formed on a film supportconsisting of biaxially orientated, crystallized linear polyestercontaining aromatic carbonyl group by the method as described above, alarge amount of an expensive solvent having high polarity and highboiling point must be incorporated in a subbing solution as the solventfor swelling or dissolving the polyester. In such case, a hightemperature and long time are required for drying the subbing layer, sothe expansion of the support and the lowering of the elasticity modulusoccur during the intial stage of the drying and thereafter, theGOntraction of the support occurs, which results in wrinkles. Moreover,when a dispersion of gelatin, as widely used as hydrophilic resin, isused as a subbing solution, it is unavoidable that the gel strength ofthe gelatin lowers and the adhesive strength under a wet condition aftercoated with a photographic emulsion is inferior.

As the solvent or swelling agent of the polyester as described above areused aldehyde or ketones having aromatic or partially saturated aromaticgroup and aldehydes having heterocyclic group containing nitrogen(U.K.P. 772,600), carboxylic acids represented by the general formula:R-COOH or R-X-COOH in which y 3,475,193 Patented Oct. 28, 1969substituted alcohols, ketones, carboxylic acids and their esters (U.K.P`797,425), benzyl alcohol whose aromatic nucleus is substituted with -NO2or -Cl U.S.P. 2,830,- 030), chloral hydrate (German Patent 1,020,457)and pyrol (German Patent 1,092,653). Illustrative of the solvents aslmentioned above are benzoic acid, salicylic acid, salicylic acid ester,monochloroacetic acid, dichloroacetic acid, trichloroacetic aid,trifluoroacetic acid, 2-nitropropanol, `benzyl alcohol, benzaldehyde,acetonyl acetone, acetophenone, benzamide, benzonitrile, benzylamine andmethyl nicotinate. Further, phenol, o-chlorophenol, cresol and otherphenol derivatives are known as the solvent or swelling agent forpolyesters.

As it has been difiicult hitherto, as mentioned hereinbefore, to form asubbing layer by applying a solution or dispersion of hydrophilic resinto a biaxially orientated, crystallized polyester, the subbing layermust be formed -by the method of applying a hydrophobic resin having agood adhesiveness and solubility to a polyester support, drying andapplying a hydrophilic resin thereto. In such subbing method, however,two layers must be provided and therefore, it is not favourable from aneconomical point of view.

The object of the present invention is to cause an emulsion layer orback layer to adhere strongly to a film support by a simple method.

That is to say, in accordance with the present invention, there is theprovision of a method of forming a subbing layer, which comprisesradiating ultraviolet rays upon a film support of biaxially orientated,crystallized linear polyester containing aromatic carbonyl groups in thepresence of oxygen and/or ozone, and then applying a subbing solution ordispersion of hydrophilic resin in an organic mixing solvent containing1-25% by weight of a solvent of swelling agent for the polyester to theradiated surface.

The film support used in our invention consists of biaxially orientated,crystallized linear polyester containing aromatic carbonyl groups, forexample, polyethylene terephthalate, copolyester of terephthalicacid-isophthalic acid-glycol and poly-l,4-cyclohexylenedirnethylterephthalate.

The organic solvent used in our invention should include 1-25% by weightof a solvent orv swelling agent for the polyester as described above asa component of the subbing solution. At above 25%, the planeness of thefilm finished is often injured, and at below 1%, the required effect ishardly given. The amount of the solvent or swelling agent for polyestermay be varied with the kind of polyester support and solvent or swellingagent, and the radiating condition. Further, it may be varied with thekind of other organic solvent coexistent. Of course, two or moresolvents or swelling agents for the polyester may be used. In this case,the amount thereof to be used is such that the total amount of the mixedsolvent or swelling agent is to be 1-25% to the whole organic solvent.

In the subbing solution used herein may be incorporated an organicsolvent-soluble hydrophilic resin, gelatin, a gelatin swelling agent,dispersing agent, an organic solvent and further additives forreinforcing the subbing layer, improving the adhesiveness between thesubbing layer and the support or emulsion layer, preventing staticcharges and coloring the support, that is to say, a hardening agent,antistatic agent, dyestuff and another hydrophilic or hydrophobic resin.In some cases, the desired adhesiveness can be obtained by the additionof a gelatin hardening agent such as ethylene imine derivative, epoxyderivative, or a hydrophobic resin such as partially saponifiedcopolymer of vinyl chloride-vinyl acetate and cellulose nitrate, even ifradiation is applied for a shorter period of time.

The hydrophilic resins used in this invention may be synthetic highmolecular compounds soluble in organic solvents and soluble in orswellable with water, said compounds containing one or more groupsselected from -OH, -COOH,

A--CO cyclic amido where R1 and R2 each represents H, -CH3, -C2H5, -C3H7or --C4Hg, -SO3M -(M represents H or an alkali metal), andnitrogen-containing heterocyclic groups. For example, there arecellulose acetate phthalate, cellulose acetate maleate, vinyl copolymercontaining maleic anhydride (e.g., copolymer of vinyl acetate and maleicanhydride 1:1), acetal mixtures containing -SO3M groups derived frompolyvinyl alcohol (cf. U.K.P. 894,- 509), acetal mixtures containing-COOM groups derived from polyvinyl alcohol, polyvinyl alcohol partiallyesterified with a divalent acid, a mixture of polyvinyl pyrrolidone andpolyacrylic acid, and the like.

In the present invention, the effective wave length of ultraviolet rayis within S200-1800 A. The use of a quartz mercury lamp leads to a goodresult practically, and if a lter absorbing ultraviolet ray having aWave length of less than 3200 A. is inserted between a film support tobe radiated and lamp, the effect by theradiation will not be observed.

The radiation of ultraviolet ray may be varied to such an extent thatthe quality of a support is not deteriorated, in accordance with thekind of a light source, the distance between a light source and filmsupport, the temperature of a film support and the kind of a medium atradiating.

The support radiated by ultraviolet ray in accordance with the inventioncan maintain a constant adhesive strength even if a subbing layer isapplied after a long storage.

In the method of our invention, the contact with a medium containingoxygen and/ or ozone may be carried out after the radiation ofultraviolet ray in vacuo or in a gas or liquid not absorbing ultravioletray so much.

The surface treatment of our invention can be without the use ofchemicals, and two or more subbings are not necessary, resulting in arapid processing. Furthermore, as the radiation of ultraviolet ray maybe carried out in the air, the apparatus and operation for carrying outthe invention are made simple and practical.

The adhesion of an emulsion layer or back layer to a support is verytenacious in our invention and is never damaged during the production,processing, use and treatment of a photographic film.

The method of our invention is carried out in general as follows:

Ultraviolet ray is radiated upon a surface of lm support of biaxiallyorientated, crystallized linear polyester by the use of an ultravioletray lamp, a subbing solution or dispersion of hydrophilic resin inorganic solvent, containing a solvent or swelling agent for thepolyester in a proportion of 1-25% to the whole OFSHHC Solvent, S

applied to the radiated surface, followed by drying and an emulsionlayer is applied thereto. In an embodiment of our invention, as shown inFIG. l, in which the radiation is carried out in the air, a biaxiallyorientated, crystallized polyester film support l of 30 cm. in width and100 microns in thickness is fed to a radiating chamber 2, where the bothsides or one side of the support is radiated by cylindrical mercurylamps 3 of quartz, l kw., 50 cm. in length and about 30 cm, in arclength, arranged apart from the support surface by about 20 cm. Theradiation time differs by the radiation conditions, but 3 minutes orless is preferable. The radiated film support is then fed to an applyingchamber 4 where it is dipped in an applying dish 5 and it is dried in adrying chamber 6, followed by being wound up. The temperature of the airin the radiating chamber can be controlled by supplying hot air or coldair thereto from the outside. The temperature at the radiating is notlimited, but a range within 70-1 50 C. is preferred. It is observed thatthe radiation at a high temperature takes a shorter time.

The tests with respect to the adhesiveness between a support andemulsion or back layer, which were carried out in the followingexamples, are the following:

Test about the dry adhesiveness-An emulsion surface of a treated anddried film or a raw film is scratched to give squares (about 4 mm. x 4mm.) by the use of razor, an adhesive tape, for example, a polyestertape manufactured by Nitto Electric Industry Co., Ltd., is pastedthereon and it is rapidly stripped therefrom. A good adhesiveness inthis test means a case where 50% or more of the emulsion layer remainson the polyester base.

Test about the wet adhesiveness during processing.- An emulsion or backsurface of a film is scratched to give a line in a processing solutionby the use of an iron pen and the surface is rubbed by a fingervertically to the line. A good adhesiveness in this test means a casewhere the emulsion or back layer is not stripped more than the scratchedline.

The present invention is further illustrated by the following examples.

EXAMPLE 1 Ultraviolet ray was radiated upon the both surfaces of Aabiaxially orientated, crystallized polyethylene terephthalate filmsupport of 3l cm. in width and 100 micron in thickness at C. for 1minute in the air by the use of a mercury lamp of quartz and l kw., anda dispersion of gelatin in organic solvents having the followingcornposition was applied thereto, followed by drying at C. for 2 minutesand Winding up.

A gelatin-silver halide emulsion layer was applied to the one side ofthe resulting subbing layer and an antihalation back layer was appliedto the other side. The adhesive strength of the photographic lightsensitive film so produced was good under a wet and dry condition.

EXAMPLE 2 The both surfaces of a biaxially orientated, crystallizedpolyethylene terephthalate film support of 31 cm. in width and 75microns in thickness were irradiated with ultraviolet ray similarly toExample l, wound and stored at normal temperature and humidity (23 C.,65% RH) for 1 month. Then, coated with a. dispersion of gelatin inorganic solvents having the following composition and dried at 120 C.for 2 minutes.

Parts by weight Gelatin c 1 Water 1 Salicylic acid 0.3 Methanol 20Acetone 60 Methylene chloride 14 IBenzyl alcohol 3 o-Chlorophenol 3 Agelatin-silver halide emulsion layer and gelatin antihalation lbacklayer were applied to the both sides respectively. The adhesivenessunder a dry and wet condition was good.

When 0.4 part of cellulose nitrate was added to the subbing solution inthis example, the subbing treatment could be carried out without anyobstacle and the adhesiveness of the product film under a dry conditionwas improved.

EXAMPLE 3 A biaxially orientated, crystallized polyethyleneterephthalate iilm support of about 1 m. width and 100 micron thicknesswas irradiated with ultraviolet ray at 100 C. for 1 minute in the air bythe use of a mercury lamp of quartz, 3 kw., 1.35 m. in length and aboutl m. in arc length, arranged apart from the support lby 30 cm.,immediately coated lwith the dispersion of gelatin in organic solvents,similar to Example l, dried and the both surfaces were coated with agelatin-silver halide emulsion. The adhesiveness under a wet and drycondition was good.

EXAMPLE 4 Parts fby weight Gelatin 1 Monochloroacetic acid 2 Phenol 6Methanol 32 Methylene chloride 60 A gelatin-silver halide emulsion wasapplied to the one side, a gelatin antihalation layer was lapplied tothe other side and dried. The adhesiveness under a wet and dry conditionwas good.

EXAMPLE 5 A biaxially orientated, crystallized polyethyleneterephthalate iilm support of 30 cm. in width was passed at 2.5 m./min.through a treating box, as shown in FIG. 2, of 120 cm. in length, 60 cm.in width and 50 cm. in depth whose inlet and outlet were sealed byrollers 7, where the one side of the iilm support 9 was irradiated at120 C. in an air containing 1% of ozone by the use of cylindricalmercury lamp 8 of 1 kw., 50 cm. in width and 30 cm. in arc length,arranged apart therefrom by 15 cm. The air containing ozone was suppliedfrom 10 and discharged from 11. The iilm support was wound up once, theradiated surface thereof was coated with the gelatin dispersion ofExample 1 by the other conventional immersion coating method and driedat 120 C. for 2 minutes. Then, the subbed surface was coated with agelatin-silver halide emulsion land dried. The adhesiveness of theproduct iilm under a dry and wet condition was good.

EXAMPLE 6 The -both surfaces of a biaxially oriented, crystallizedpolyethylene terephthalate iilm support of 100g in thickness and 31 cm.in width were irradiated by ultraviolet rays for 1 minute at 80 C. inthe air using a quartz mercury lamp of 1 kw., coated immediately with ahydrophilic resin solution having the following composition, and afterdrying for 3 minutes at 100 C., the film support was rolled up.

Weight parts Maleic anhydride-vinyl acetate copolymer (1:1) 1.3

Methanol 45 Acetone 25 Methylene chloride 20 Monochloroacetic acid 10Chromium acetate 0.4

On the one side of thus subbed surfaces of the film support was applieda gelatino silver halide emulsion and on the opposite an anti-halationback layer, and they were dried. The adhesiveness of thus obtainedphotosensitive film under wet and dry conditions was good.

EXAMPLE 7 =Parts by weight Mixed acetal of polyvinyl alcohol 1 1Methanol 30 Acetone 60 Benzyl alcohol 5 o-Chlorophenol 5 1Polyvnylalcohol mixed-acetalated with (I) benzaldehyde and (II) a sodium salt ofbenzaldehyde-Q-sulfonic acid (I, 25%; II, 45%; -OH, 30%).

On the both surfaces of the Iiilm base were coated a gelatino silverhalide emulsion layer and a gelatino antihalation back layerrespectively and they were dried. The adhesive property of the layers ina dry state and a wet state was good.

EXAMPLE 8 The both surfaces of a biaxially oriented, crystallizedpoly-l,4-cyclohexylenedimethylterephthalate film support was irradiatedfor 2 minutes at 100 C. in the air by a quartz mercury lamp of l kw.,immediately coated with the subbing solution having the followingcomposition, and dried for 2 minutes at 120 C.

-Parts by weight Copolymer of diethylacrylamide (66%) and methacrylicacid (34%) 1.5 Methanol 45 Acetone 35 Methylene chloride 10o-Chlorophenol 10 Chromium acetate 0.5

On the both surfaces of thus subbed film support were coated a gelatinosilver halide emulsion layer and a gelatino antihalation layerrespectively, and they were dried. The adhesive property of the layersin dry and wet states was good.

What is claimed is:

1. A process for subbing a photographic film, which comprises radiatingultraviolet rays having wave lengths of 1800 to 3200 A. for a durationof up to 3 minutes upon a film support of biaxially oriented,crystallized linear polyester containing aromatic carbonyl groups, inthe presence of at least one member selected from the group consistingof oxygen and ozone, applying to the radiated surface of the filmsupport a subbing solution containing a member selected from the groupconsisting of gelatin and a hydrophilic organic solvent-soluble resinand also containing a mixed organic solvent containing l-25% by weightof a solvent for the polyester drying, applying a gelatino silver halideemulsion to said subbed surface and then drying.

2. The process according to claim 1, wherein the linear polyester ispolyethylene terephthalate.

3. The process according to claim 1, wherein the sub- Ibing solutioncontains gelatin.

4. The process according to claim 1, wherein the sub- 10 bing solutioncontains a member selected from the group consisting of a maleicanhydride-vinyl acetate copolymer, a mixed acetal of polyvinyl alcoholand a copolymer of diethylacrylamide and methacrylic acid.

5. The process according to claim 1 wherein said subbing solution isapplied to both sides of said film, and

wherein the gelatino silver 4halide emulsion is applied to one side ofsaid subbed film, and a gelatino antihalation layer is applied to theother side of said subbed film.

References Cited UNITED STATES PATENTS 2,805,173 9/1957 Ambler 117-472,876,187 3/1959 Wolnski 117-47 3,337,364 8/1967 Whitbourne 1l7l38.8

MURRAY KATZ, Primary Examiner U.S. Cl. X.R.

